Patents by Inventor Bhadri N. Varadarajan

Bhadri N. Varadarajan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20180096842
    Abstract: Provided are methods and apparatuses for depositing a graded or multi-layered silicon carbide film using remote plasma. A graded or multi-layered silicon carbide film can be formed under process conditions that provide one or more organosilicon precursors onto a substrate in a reaction chamber. Radicals of source gas in a substantially low energy state, such as radicals of hydrogen in the ground state, are provided from a remote plasma source into reaction chamber. In addition, co-reactant gas is flowed towards the reaction chamber. In some implementations, radicals of the co-reactant gas are provided from the remote plasma source into the reaction chamber. A flow rate of the co-reactant gas can be changed over time, incrementally or gradually, to form a multi-layered silicon carbide film or a graded silicon carbide film having a composition gradient from a first surface to a second surface of the graded silicon carbide film.
    Type: Application
    Filed: September 30, 2016
    Publication date: April 5, 2018
    Inventors: Bhadri N. Varadarajan, Bo Gong, Guangbi Yuan, Zhe Gui, Fengyuan Lai
  • Publication number: 20180044791
    Abstract: Certain embodiments herein relate to an apparatus used for remote plasma processing. In various embodiments, the apparatus includes a reaction chamber that is conditioned by forming a low recombination material coating on interior chamber surfaces. The low recombination material helps minimize the degree of radical recombination that occurs when the reaction chamber is used to process substrates. During processing on substrates, the low recombination material may become covered by relatively higher recombination material (e.g., as a byproduct of the substrate processing), which results in a decrease in the amount of radicals available to process the substrate over time. The low recombination material coating may be reconditioned through exposure to an oxidizing plasma, which acts to reform the low recombination material coating. The reconditioning process may occur periodically as additional processing occurs on substrates.
    Type: Application
    Filed: October 26, 2017
    Publication date: February 15, 2018
    Inventors: Bhadri N. Varadarajan, Bo Gong, Rachel E. Batzer, Huatan Qiu, Bart J. van Schravendijk, Geoffrey Hohn
  • Publication number: 20180004083
    Abstract: Vacuum-integrated photoresist-less methods and apparatuses for forming metal hardmasks can provide sub-30 nm patterning resolution. A metal-containing (e.g., metal salt or organometallic compound) film that is sensitive to a patterning agent is deposited on a semiconductor substrate. The metal-containing film is then patterned directly (i.e., without the use of a photoresist) by exposure to the patterning agent in a vacuum ambient to form the metal mask. For example, the metal-containing film is photosensitive and the patterning is conducted using sub-30 nm wavelength optical lithography, such as EUV lithography.
    Type: Application
    Filed: August 30, 2017
    Publication date: January 4, 2018
    Inventors: Jeffrey Marks, George Andrew Antonelli, Richard A. Gottscho, Dennis M. Hausmann, Adrien LaVoie, Thomas Joseph Knisley, Sirish K. Reddy, Bhadri N. Varadarajan, Artur Kolics
  • Publication number: 20170365462
    Abstract: Disclosed are methods and systems for providing oxygen doped silicon carbide. A layer of oxygen doped silicon carbide can be provided under process conditions that employ one or more silicon-containing precursors that have one or more silicon-hydrogen bonds and/or silicon-silicon bonds. The silicon-containing precursors may also have one or more silicon-oxygen bonds and/or silicon-carbon bonds. One or more radical species in a substantially low energy state can react with the silicon-containing precursors to form the oxygen doped silicon carbide film. The one or more radical species can be formed in a remote plasma source.
    Type: Application
    Filed: September 5, 2017
    Publication date: December 21, 2017
    Inventor: Bhadri N. Varadarajan
  • Patent number: 9837270
    Abstract: Provided are methods and apparatuses for densifying a silicon carbide film using remote plasma treatment. Operations of remote plasma deposition and remote plasma treatment of the silicon carbide film alternatingly occur to control film density. A first thickness of silicon carbide film is deposited followed by a remote plasma treatment, and then a second thickness of silicon carbide film is deposited followed by another remote plasma treatment. The remote plasma treatment can flow radicals of source gas in a substantially low energy state, such as radicals of hydrogen in a ground state, towards silicon carbide film deposited on a substrate. The radicals of source gas in the substantially low energy state promote cross-linking and film densification in the silicon carbide film.
    Type: Grant
    Filed: December 16, 2016
    Date of Patent: December 5, 2017
    Assignee: Lam Research Corporation
    Inventors: Bhadri N. Varadarajan, Bo Gong, Guangbi Yuan, Zhe Gui, Fengyuan Lai
  • Patent number: 9828672
    Abstract: Methods and apparatus for remote plasma processing are provided. In various embodiments, a reaction chamber is conditioned by forming a low recombination material coating on interior chamber surfaces. The low recombination material helps minimize the degree of radical recombination that occurs within the reaction chamber when the reaction chamber is used to process substrates. During processing on substrates, the low recombination material may become covered by relatively higher recombination material (e.g., as a byproduct of the substrate processing), which results in a decrease in the amount of radicals available to process the substrate over time. The low recombination material coating may be reconditioned through exposure to an oxidizing plasma, which acts to reform the low recombination material coating. The reconditioning process may occur periodically as additional processing occurs on substrates.
    Type: Grant
    Filed: May 14, 2015
    Date of Patent: November 28, 2017
    Assignee: Lam Research Corporation
    Inventors: Bhadri N. Varadarajan, Bo Gong, Rachel E. Batzer, Huatan Qiu, Bart J. van Schravendijk, Geoffrey Hohn
  • Publication number: 20170323803
    Abstract: Methods and apparatuses suitable for depositing low hydrogen content, hermetic, thin encapsulation layers at temperatures less than about 300° C. are provided herein. Methods involve pulsing plasma while exposing a substrate to deposition reactants, and post-treating deposited encapsulation films to densify and reduce hydrogen content. Post-treatment methods include periodic exposure to inert plasma without reactants and exposure to ultraviolet radiation at a substrate temperature less than about 300° C.
    Type: Application
    Filed: September 28, 2016
    Publication date: November 9, 2017
    Inventors: Bart J. van Schravendijk, Akhil Singhal, Joseph Hung-chi Wei, Bhadri N. Varadarajan, Kevin M. McLaughlin, Casey Holder, Ananda K. Banerji
  • Patent number: 9778561
    Abstract: Vacuum-integrated photoresist-less methods and apparatuses for forming metal hardmasks can provide sub-30 nm patterning resolution. A metal-containing (e.g., metal salt or organometallic compound) film that is sensitive to a patterning agent is deposited on a semiconductor substrate. The metal-containing film is then patterned directly (i.e., without the use of a photoresist) by exposure to the patterning agent in a vacuum ambient to form the metal mask. For example, the metal-containing film is photosensitive and the patterning is conducted using sub-30 nm wavelength optical lithography, such as EUV lithography.
    Type: Grant
    Filed: January 30, 2015
    Date of Patent: October 3, 2017
    Assignee: LAM RESEARCH CORPORATION
    Inventors: Jeffrey Marks, George Andrew Antonelli, Richard A. Gottscho, Dennis M. Hausmann, Adrien LaVoie, Thomas Joseph Knisley, Sirish K. Reddy, Bhadri N. Varadarajan, Artur Kolics
  • Publication number: 20170092856
    Abstract: Methods of depositing silicon nitride encapsulation layers by atomic layer deposition over memory devices including chalcogenide material are provided herein. Methods include using iodine-containing silicon precursors and depositing thermally using ammonia or hydrazine as a second reactant, or iodine-containing silicon precursors and depositing using a nitrogen-based or hydrogen-based plasma.
    Type: Application
    Filed: November 6, 2015
    Publication date: March 30, 2017
    Inventors: Jon Henri, Dennis M. Hausmann, Seshasayee Varadarajan, Bhadri N. Varadarajan
  • Patent number: 9601693
    Abstract: Methods of depositing silicon nitride encapsulation layers by atomic layer deposition over memory devices including chalcogenide material are provided herein. Methods include using iodine-containing silicon precursors and depositing thermally using ammonia or hydrazine as a second reactant, or iodine-containing silicon precursors and depositing using a nitrogen-based or hydrogen-based plasma.
    Type: Grant
    Filed: November 6, 2015
    Date of Patent: March 21, 2017
    Assignee: Lam Research Corporation
    Inventors: Jon Henri, Dennis M. Hausmann, Seshasayee Varadarajan, Bhadri N. Varadarajan
  • Publication number: 20160379826
    Abstract: Disclosed herein are methods of doping a fin-shaped channel region of a partially fabricated 3-D transistor on a semiconductor substrate. The methods may include forming a multi-layer dopant-containing film on the substrate, forming a capping film comprising a silicon carbide material, a silicon nitride material, a silicon carbonitride material, or a combination thereof, the capping film located such that the multi-layer dopant-containing film is located in between the substrate and the capping film, and driving dopant from the dopant-containing film into the fin-shaped channel region. Multiple dopant-containing layers of the film may be formed by an atomic layer deposition process which includes adsorbing a dopant-containing film precursor such that it forms an adsorption-limited layer on the substrate and reacting adsorbed dopant-containing film precursor.
    Type: Application
    Filed: February 28, 2014
    Publication date: December 29, 2016
    Inventors: Reza Arghavani, Samantha Tan, Bhadri N. Varadarajan, Adrien LaVoie, Ananda Banerji, Jun Qian, Shankar Swaminathan
  • Publication number: 20160281230
    Abstract: Certain embodiments herein relate to methods of conditioning a reaction chamber that is used for remote plasma processing. Other embodiments herein relate to apparatus used for remote plasma processing. In various embodiments, a reaction chamber is conditioned by forming a low recombination material coating on interior chamber surfaces. The low recombination material helps minimize the degree of radical recombination that occurs within the reaction chamber when the reaction chamber is used to process substrates. During processing on substrates, the low recombination material may become covered by relatively higher recombination material (e.g., as a byproduct of the substrate processing), which results in a decrease in the amount of radicals available to process the substrate over time. The low recombination material coating may be reconditioned through exposure to an oxidizing plasma, which acts to reform the low recombination material coating.
    Type: Application
    Filed: May 14, 2015
    Publication date: September 29, 2016
    Inventors: Bhadri N. Varadarajan, Bo Gong, Rachel E. Batzer, Huatan Qiu, Bart J. van Schravendijk, Geoffrey Hohn
  • Publication number: 20160276140
    Abstract: A thin layer of a silicon-carbon-containing film is deposited on a substrate by generating hydrogen radicals from hydrogen gas supplied to a radicals generation chamber, supplying the hydrogen radicals to a substrate processing chamber separate from the substrate processing chamber via a multiport gas distributor, and reacting the hydrogen radicals therein with an organosilicon reactant introduced into the substrate processing chamber concurrently. The hydrogen radicals are allowed to relax into a ground state in a radicals relaxation zone within the substrate processing chamber before reacting with the organosilicon reactant.
    Type: Application
    Filed: May 31, 2016
    Publication date: September 22, 2016
    Inventors: Bhadri N. Varadarajan, Bo Gong
  • Patent number: 9418889
    Abstract: A dielectric diffusion barrier is deposited on a substrate that has a via and an overlying trench etched into an exposed layer of inter-layer dielectric, wherein there is exposed metal from the underlying interconnect at the bottom of the via. In order to provide a conductive path from the underlying metallization layer to the metallization layer that is being formed over it, the dielectric diffusion barrier is formed selectively on the inter-layer dielectric and not on the exposed metal at the bottom of the via. In one example a dielectric SiNC diffusion barrier layer is selectively deposited on the inter-layer dielectric using a remote plasma deposition and a precursor that contains both silicon and nitrogen atoms. Generally, a variety of dielectric diffusion barrier materials with dielectric constants of between about 3.0-20.0 can be selectively formed on inter-layer dielectric.
    Type: Grant
    Filed: June 17, 2015
    Date of Patent: August 16, 2016
    Assignee: Lam Research Corporation
    Inventors: Thomas Weller Mountsier, Hui-Jung Wu, Bhadri N. Varadarajan, Nagraj Shankar, William T. Lee
  • Patent number: 9371579
    Abstract: A thin layer of a silicon-carbon-containing film is deposited on a substrate by generating hydrogen radicals from hydrogen gas supplied to a radicals generation chamber, supplying the hydrogen radicals to a substrate processing chamber separate from the substrate processing chamber via a multiport gas distributor, and reacting the hydrogen radicals therein with an organosilicon reactant introduced into the substrate processing chamber concurrently. The hydrogen radicals are allowed to relax into a ground state in a radicals relaxation zone within the substrate processing chamber before reacting with the organosilicon reactant.
    Type: Grant
    Filed: October 24, 2013
    Date of Patent: June 21, 2016
    Assignee: Lam Research Corporation
    Inventors: Bhadri N. Varadarajan, Bo Gong
  • Publication number: 20160090649
    Abstract: Provided are methods and systems for providing silicon carbide class of films. The composition of the silicon carbide film can be controlled by the choice of the combination of precursors and the ratio of flow rates between the precursors. The silicon carbide films can be deposited on a substrate by flowing two different organo-silicon precursors to mix together in a reaction chamber. The organo-silicon precursors react with one or more radicals in a substantially low energy state to form the silicon carbide film. The one or more radicals can be formed in a remote plasma source.
    Type: Application
    Filed: December 7, 2015
    Publication date: March 31, 2016
    Inventor: Bhadri N. Varadarajan
  • Patent number: 9234276
    Abstract: Provided are methods and systems for providing silicon carbide class of films. The composition of the silicon carbide film can be controlled by the choice of the combination of precursors and the ratio of flow rates between the precursors. The silicon carbide films can be deposited on a substrate by flowing two different organo-silicon precursors to mix together in a reaction chamber. The organo-silicon precursors react with one or more radicals in a substantially low energy state to form the silicon carbide film. The one or more radicals can be formed in a remote plasma source.
    Type: Grant
    Filed: May 31, 2013
    Date of Patent: January 12, 2016
    Assignee: Novellus Systems, Inc.
    Inventor: Bhadri N. Varadarajan
  • Publication number: 20150380302
    Abstract: A dielectric diffusion barrier is deposited on a substrate that has a via and an overlying trench etched into an exposed layer of inter-layer dielectric, wherein there is exposed metal from the underlying interconnect at the bottom of the via. In order to provide a conductive path from the underlying metallization layer to the metallization layer that is being formed over it, the dielectric diffusion barrier is formed selectively on the inter-layer dielectric and not on the exposed metal at the bottom of the via. In one example a dielectric SiNC diffusion barrier layer is selectively deposited on the inter-layer dielectric using a remote plasma deposition and a precursor that contains both silicon and nitrogen atoms. Generally, a variety of dielectric diffusion barrier materials with dielectric constants of between about 3.0-20.0 can be selectively formed on inter-layer dielectric.
    Type: Application
    Filed: June 17, 2015
    Publication date: December 31, 2015
    Inventors: Thomas Weller Mountsier, Hui-Jung Wu, Bhadri N. Varadarajan, Nagraj Shankar, William T. Lee
  • Publication number: 20150303056
    Abstract: Disclosed are methods and systems for providing silicon carbide films. A layer of silicon carbide can be provided under process conditions that employ one or more silicon-containing precursors that have one or more silicon-hydrogen bonds and/or silicon-silicon bonds. The silicon-containing precursors may also have one or more silicon-oxygen bonds and/or silicon-carbon bonds. One or more radical species in a substantially low energy state can react with the silicon-containing precursors to form the silicon carbide film. The one or more radical species can be formed in a remote plasma source.
    Type: Application
    Filed: February 6, 2015
    Publication date: October 22, 2015
    Inventors: Bhadri N. Varadarajan, Bo Gong, Zhe Gui
  • Patent number: 9147589
    Abstract: A processing system includes a chamber and a steam source that supplies steam in the chamber. A UV source directs UV light onto a deposited layer of a substrate in the presence of the steam from the steam source for a predetermined conversion period to at least partially convert the deposited layer.
    Type: Grant
    Filed: July 31, 2013
    Date of Patent: September 29, 2015
    Assignee: NOVELLUS SYSTEMS, INC.
    Inventors: Bhadri N Varadarajan, Bart Van Schravendijk